GATE 1987 Electronics & Communication

A thin dipole antenna is $$\left( {\lambda /15} \right)$$ long, where $$\lambda $$ is the voperating wavelength. If the dipole has a loss resistance of $$1.5$$ ohm determine its (i...

A transmission line of pure resistive characteristic impedance is terminated with an unknown load. The measured value of VSWR on the line is equal to 2 and a voltage minimum point...

Given that for a logic family, $${V_{OH}}$$ is the minimum output high-level voltage $${V_{OL}}$$ is the minimum output low-level voltage $${V_{IH}}$$ is the minimum output high-le...

The subtraction of a binary number Y from another binary number X, done by adding the 2's complement of Y to X, result in a binary number without overflow. This implies that the re...

For the system shown in figure the transfer function $$\frac{\mathrm C\left(\mathrm s\right)}{\mathrm R\left(\mathrm s\right)}$$ is equal to

The popular plot of G(s)=$${{10} \over {s{{\left( {s + 1} \right)}^2}}},$$ intercepts real axix at $$\omega = {\omega _0}$$ Then, the real part and $${\omega _0}$$ are respectively...

A rectangular pulse existing between t = 0 and t = T and having an amplitude A is to be received by a matched filter (a) Draw the impulse response of the matched filter labeling al...

Companding in PCM systems leads to improved signal - to - quantization noise ratio. This improvement is for

White Gaussian noise is passed through a linear narrow band filter. The probability density function of the envelope of the noise at the filter output is:

The cut-off frequency of a waveguide depends upon

An electric field is given by $$\overrightarrow E = \overrightarrow a {}_x\,{\rm A}\,\,\sin \,\beta ySin\,\,\omega t$$ is present in a charge free medium infinite in extent (a) Det...

For an electromagnetic wave incident from one medium to a second medium, total reflection takes place when

An electrostatic field is said to be conservative when

The variance of a random variable X is $$\sigma _x^2\,.$$ Then the variance of - kx (where k is a positive constant ) is

A system has fourteen poles and two zeroes. Its high frequency asymptote, in its magnitude plot, has having a slope of

In case of class A amplifiers, the ratio (efficiency of transformer coupled amplifier)/(efficiency of a transformer less amplifier ) is

The impedance function of a parallel $$R$$, $$L$$, $$C$$ circuit has poles located at $$ - 3 \pm j4$$ rad/sec. If the value of $$L = 1H$$, determine the following: (a) the values o...

Fill in the blanks of the statements below concerning the following Logic Families: Standard TTL (74XX), Low power TTL(74LXX) Low power schottky TTL(74LSXX), schottky TTL(74 SXXX),...

In an intrinsic semiconductor the free electron concentration depends on

The diffusion capacitance of a P-N junction

Laplace transform of the functions t u(t) and u(t) sin(t) are respectively: